The primary purpose of any network is to provide a method to communicate information. From the very earliest primitive humans to the most advanced scientists of today, sharing information with others is crucial for human advancement.
All communication begins with a message, or information, that must be sent from one individual or device to another. The methods used to send, receive and interpret messages change over time as technology advances.
All communication methods have three elements in common.
The first of these elements is the message source, or sender. Message sources are people, or electronic devices, that need to communicate a message to other individuals or devices.
The second element of communication is the destination, or receiver, of the message. The destination receives the message and interprets it. A third element, called a channel, provides the pathway over which the message can travel from source to destination.
In any conversation between two people, there are many rules, or protocols, that the two must follow in order for the message to be successfully delivered and understood. Among the protocols for successful human communication are:
- Identification of sender and receiver
- Agreed-upon medium or channel (face-to-face, telephone, letter, photograph)
- Appropriate communication mode (spoken, written, illustrated, interactive or one-way)
- Common language
- Grammar and sentence structure
- Speed and timing of delivery
Imagine what would happen if no protocols or rules existed to govern how people communicate with each other. Would you be able to understand them? Are you able to read the paragraph that does not follow commonly accepted protocols?
Protocols are specific to the characteristics of the source, channel and destination of the message. The rules used to communicate over one medium, like a telephone call, are not necessarily the same as communication using another medium, such as a letter.
Protocols define the details of how the message is transmitted, and delivered.
This includes issues of:
- Message format (formato)
- Message size (dimensioni)
- Timing (sincronizzazione)
- Encapsulation (formattazione)
- Encoding (codifica)
- Standard message pattern (tipi di canali)
Many of the concepts and rules that make human communication reliable and understandable also apply to computer communication*.
* We know all these rules and apply them in every automatic system but not often we focus on them while life flows.